You probably know what Firefox extensions are and how they work. Here's the quick-and-dirty definition, from the Fox's mouth:

Extensions are small add-ons that add new functionality to Firefox. They can add anything from a toolbar button to a completely new feature. They allow the application to be customized to fit the personal needs of each user if they need additional features, while keeping Firefox small to download.

The last time I checked, more than 970 extensions were available for download through addons.mozilla.org: Mozilla's official online source for All Things Firefox, also known as "AMO" to frequent visitors and lazy writers.

Click around AMO for a few minutes, and you'll get an idea of just how much creativity and hard work Mozilla has inspired among Firefox users. I won't bore you here with any lectures on the benefits of open-source software -- it's enough to know that you're looking at one of them, or rather hundreds of them, right on that site.

Picking your first extensions is a tough job; there are people who wandered into AMO's digital labyrinth months ago, and they're still in there. If you find it tough to eat just one potato chip, there's a good chance that trying to install just one extension will make your head explode.

Spare your sanity (and the curtains): Start with these key Firefox extensions that belong on every user's desktop. Even if you decide for some reason to run without them, knowing about these extensions is a matter of basic Firefox literacy -- and disabling or uninstalling them takes a matter of seconds.

(Hint: If you're an impatient sort, you can jump directly to our Quick-Click Chart to download without the details.)

Want More?

Believe it or not, this article barely scratches the surface of Mozilla's add-on architecture for Firefox. For an in-depth look at the latest, coolest, and lamest extensions, check out Scot Finnie's ongoing coverage of the Best Firefox Extensions And Customizing Tips. You'll also find links to useful Firefox-related sites and timely how-to content -- and best of all, Scot's site never dispenses advice older than the magazines in your dentist's waiting room.

For a basic guide to installing Firefox extensions, don't waste your time wandering the Web -- look no further than the browser's own Help menu, under "Customization: Extensions" in the Contents list. If things begin to get weird (they probably won't), Scot's brief tutorial on How To Install Firefox Extensions will get you back on the right path.

Adblock Plus With Filterset.G Updater
The original Adblock extension isn't just popular; it's THE reason why some people switch to Firefox in the first place. It's easy to see why: For every tasteful, thoughtful online ad, there are ten blinking, neon-colored insults to your intelligence -- and each one of them wastes a little more of your time and bandwidth.

Here's what you'll see without Adblock Plus.Click image to enlarge and to launch image gallery.

In recent months, however, the original Adblock has piled on the new features for power users. Unfortunately, that means it's also getting a bit bloated, runs more slowly, and has wrestled more than its share of compatibility problems in recent months.

Here's my advice: Start instead with the latest version of Adblock Plus. Like Adblock, it turns Web pages into something that doesn't require a Dramamine patch to view without losing your lunch.

Unlike Adblock, it's designed to be lightning-quick, lightweight, and easy to use -- and since taking over Adblock Plus just a few days ago, the new developer, Wladimir Palant, has already taken some big steps towards these goals. Until you need more, this is the banner-ad management tool that belongs in your Firefox toolkit.

The Straight Dope On Adblock Plus

In the days following the handoff of Adblock Plus from the previous developer to his replacement, Wladimir Palant, there has been a lot of confusion, and a discouraging amount of ignorance and FUD, concerning both the project and Wladimir himself.

Here's what you need to know, before you encounter any misinformation in the AMO forums: The Adblock Plus project handoff was a voluntary and mutually agreed-upon event, and Wladimir Palant has already earned a lot of praise for his work on Adblock Plus from his predecessor, other developers, and longtime Firefox users.

Please take any comments on the AMO user forums that attack either Adblock Plus or its new developer with a very, very big grain of salt. These kinds of misunderstandings are unfortunate and very annoying when they get out of control, and they are inherently unfair to developers who may be too busy even to notice such comments, much less respond to them.

The perfect Adblock Plus setup includes one more ingredient: the one and only Adblock Filterset.G Updater. Named with its creator's initial tacked onto the end, this is a pre-compiled set of regular expressions to filter and catch virtually every banner ad before Firefox wastes your bandwidth downloading it.

The same page after Adblock Plus and Filterset.G have done their thing.Click image to enlarge and to launch image gallery.

Filterset.G, a set of filters maintained for Adblock, will, if you give it the OK during its first startup, update itself about once a week. In addition, both Filterset.G and Adblock Plus 0.6 now support whitelisting -- a great way to support and thank sites that put their users first. All in all, I consider Filterset.G every bit as essential to the Firefox experience as the Adblock Plus extension itself.

FlashBlock
The sheer quantity of bad Flash content choking the Web these days is enough to make me wonder if there's a guy with horns and a pointy tail sitting on the Macromedia (whoops, make that Adobe) board of directors. Enter FlashBlock, which allows you, and not some design-challenged satanic dimbulb, to decide whether or not to load a given piece of Flash content.

Macromedia isn't the worst offender, but there's still more Flash on its home page than most of us want or need.Click image to enlarge and to launch image gallery.

If you've ever watched a bloated piece of Flash trash slow your system to a crawl, only to serve up a silly banner ad or a souvenir from some designer's ego trip, this extension will put a smile on your face faster than you can say "exorcism." And as with Adblock Plus, you'll find a whitelist option (just open the Extensions Manager under the Tools menu, select the extension, and click Options) to allow well-behaved sites to load Flash without a detour through purgatory.

FlashBlock makes the Web a calmer place.Click image to enlarge and to launch image gallery.

Disable Targets For Downloads
This diminutive extension weighs in at just 10KB, and it serves exactly one purpose: Keeping a new browser tab or window from opening for no reason when you download files.

It's a little thing, but it drives me nuts -- and a lot of people feel the same way. In terms of benefit-to-size ratio, I can't not recommend Disable Targets For Downloads as an essential part of every Firefox setup.

History Menu
This is another small-footprint extension (just 7KB) that adds a set of submenus -- one for each day, going back a week -- below the standard list of your last 10 visited Web sites under the Firefox "Go" menu.

Simple, but solid: History Menu makes your history menu more useful.Click image to enlarge and to launch image gallery.

You'll find other extensions that add much, much more to your History menu, and some of them are quite good. But if you're looking for a fast, elegant, effective extension that will benefit just about any Firefox user without piling on the bells and whistles, this is the one you need.

Tab Mix Plus
Firefox has spawned a whole category of extensions devoted to tweaking one of the browser's most popular and practical features: tabbed browsing. Yet this cornucopia hides more than its share of bad apples: Some tab-management extensions are notorious for breaking themselves, other extensions, and Firefox itself if you even look at them the wrong way.

Tab Mix Plus sounds like a brand of cat food -- but believe me, your cat should have it this good. This is the first Firefox tab-management tool that really delivers the goods, minus any drama, rude surprises, or smoking craters where your profile folder used to sit.

My favorite feature, the ability to undo a tab you accidentally closed, even restores your tabs following a browser crash. This is a double bonus, since it provides an alternative to the migraine-inducing Session Saver extension -- a time-wasting pain in the butt I wouldn't recommend to anyone whom I wouldn't also encourage to try the salmon mousse.

Download Manager Tweak
Some extensions are so well-built, practical, and just plain smart that it's a pity they aren't built into Firefox itself. This is one of them: With Download Manager Tweak you can choose where the Download Manager opens, change the buttons that appear within it, and make other surprisingly handy changes. It's not flashy and certainly not complicated, but it may very well be the quintessential Firefox extension anyway.

Download Manager Tweak turns one of Firefox's least interesting features into a surprisingly useful and practical tool.Click image to enlarge and launch image gallery.

IE View Lite
Sites that don't display properly on Firefox are getting scarce these days, and the best way to persuade the holdouts is to take your business elsewhere. But when you really need to see a site that requires Internet Explorer, IE View Lite provides convenient, one-click access to IE for a selected or the current page.

There is, of course, also the original IE View, and there's also a new IE Tab extension that does the same thing as a tab within Firefox itself. Both of these extensions use C++ code to do their thing, which means they use DLLs -- which means they're larger than the JavaScript-based IE View Lite and more susceptible to changes not only in Firefox but in Windows itself. Here, too, I think it's better to start small and then move up later, if necessary.

Also, remember: A site that is harmless to Firefox could spring some nasty surprises when Internet Explorer comes calling. Be sure your IE software is up to date, keep its security options properly configured, and use good judgment before sending your second-string browser into the game.

Fasterfox
Since its earliest days, Firefox has included the ability to tweak its networking settings, including some that are either inactive or set below their maximum capacity, depending on the version. Changing some of these settings, in the right combinations, can make Firefox noticeably faster at rendering pages.

Fasterfox allows you, with one click, to make all of the changes required to boost page rendering speed -- in relative terms, from slowest (the default settings) to the fastest possible results.

Speed up your surfing (but not too much) with Fasterfox.Click image to enlarge and to launch image gallery.

Why not simply peg these settings at "warp speed" and forget about them? Because some of them, such as prefetching, can sometimes overload Web servers, saturate a site's bandwidth, and turn a site admin into someone you don't want to meet in a dark alley. Although very few sites will try to ban or even scold users with over-aggressive Fasterfox settings, use your power wisely -- pick one of the more "polite" middle settings, and spend the karma you save on a nice parking spot.

PasswordMaker
The Firefox password manager is acceptable, but you can do better -- thanks to an extension based on some high-powered applied mathematics. The fact that PasswordMaker delivers this cryptographic complexity in a package even a head-injured monkey could use just makes it even more impressive.

What does that mean to you? In the words of its developers, PasswordMaker "creates unique, secure passwords that are very easy for you to retrieve but no one else. Nothing is stored anywhere, anytime, so there's nothing to be hacked, lost, or stolen." Once you've set up a master password with this extension, it performs a mathematical operation using your master password and the URL of the site being managed, which in turn generates your unique password for that particular site.

Better yet, you can use PasswordMaker to log into sites anywhere, on any browser, courtesy of an online version of the product. All you need is your master password.

PasswordMaker uses your master password and the URL of the site you're visiting to create a unique password for that site.Click image to enlarge and to launch image gallery.

If you want to know more about the extension and the science behind it -- and you really should, it's your passwords we're talking about here -- the developers do a great job explaining how it all works. As far as I'm concerned, either you're using this extension to manage your Firefox passwords, or you're cruisin' for a bruisin'.

Search Plug-Ins
Firefox extensions are a remarkably addictive habit. They also steal the spotlight from another, closely related Firefox feature that also offers a fascinating, and seemingly endless, supply of new choices: search plug-ins.

By default, Firefox installs with a search box visible at the top right of your browser window. If you don't see it, simply click View > Toolbars > Customize. Scroll down the resulting collection of draggable user interface components (which gives you plenty of other interesting options -- be sure to return later to explore it), click and hold your mouse button over the search box component, and then drag it anyplace on the Firefox toolbar that you care to place it.

Drag the search box component onto your toolbar.

Now, click on the search drop-down menu arrow at the left end of the search box. You'll see a list of a half-dozen or so search options listed; click on one of them, and it becomes your default search option.

Next, click Add Engines, which will take you to the search engine add-on page at AMO. You'll find a couple dozen additional search engine options, any of which you can install in your search box pull-down menu by clicking on its link.

Just click one of the many search engine add-ons that Mozilla makes available to add it to your search drop-down menu.Click image to enlarge and launch image gallery.

The real fun, however, begins when you click on the link at the bottom of the page, which takes you to mycroft.mozdev.org: the keepers of Mozilla's search engine treasure trove. You'll find a few more search add-on options here -- 5,649 of them, to be more precise, as of my last visit. Besides a search tool to help you sort through all these search tools, you'll find links to still more helpful search-related sites.

And don't forget the SearchPluginHacks extension, which corrects one of the not-so-cool things about search add-ons: the fact that Firefox doesn't give you a reliable way to uninstall add-ons you no longer want cluttering the search menu.

Spare you the details; you just want the goods? Here you go -- a quick-reference chart of the must-have extensions on our list.

If you're good at counting, you'll quickly realize there are eleven extensions here. That's because the first two -- Adblock Plus and Adblock Filterset.G Updater -- go hand in hand; we count them as one extension in two parts.

The information on this chart is current as of January 2006. Minor details may change as new versions are released.

Matt McKenzie is the editor of Linux Pipeline. Over the years, he has broken more PC hardware than most people will ever use -- and he's not done yet. Contact him at mattcmp@sonic.net with questions, comments, complaints, or cash.

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